Enlarging easel



Dec. 1, 1953 J KEINATH ET AL 2,660,919

ENLARGING EASEL Filed Aug. 10 1950 3 Sheets-Sheet l INVENTORS JOHANNES K. ATH, MANFRED K 1' FRIEDHELM B088 and Luowls LEITZ.

Dec. 1, 1953 J. KEINATH ETAL ENLARGING EASEL 5 Sheets-Sheet 3 Filed Aug. 10 1950 Bab INVENTORS JOHANNES KEINAT MANFRED KU FRIEDHELM HN, B038 and LUDWIG LEITZ.

Fatenteci Dec. 1, 1953 ENLARGIN G EASEL Johannes Keinath,

helm Boss, Onstmett Wetzlar (Lahn), Germany,

Manfred Kiihn, and Friedingen, and Ludwig Leitz,

assignors to Ernst Leitz G. in. b. H., Wetziar, Germany, a corporation of Germany Application Augustlil, 1950, Serial No. 178,574

Claims priority, application Germany August 11, 1949 2 Claims.

This invention with ejector of the photographic Paper. t of this invention is to provicle an ich facilitates and accelerates the real of photographic enlargements. The

preferred. embed ent of the invention enables, moreover. one-sh ned operators to use the enlarging easel. The easel comprises all elements necessary to operation and can be used in connection with every enlarging device that is adjustable relative to the base plate.

it a i'najor object of the invention to provide a new enlarging easel wherein an electr0- 'agnetio operates raising and lowering the hacking frame, the latter being pivotally mounted to brackets on the base plate and fitted with adjustable hands defining the size of the picture.

It another object of the present invention to provide a new enlarging easel wherein the enla ng paper positioned on the base plate ish upon the surface thereof and is held vtron before the masking frame is closed, whereby the clamping device is engaged to the stop members donning the width of margins of the photographic paper to be inserted.

It is a further object of the present invention to provide a new enlarging easel wherein the hereina ove mentioned clamping device is concomitan developed as ejector of the exposed photographic paper, both, clamping device and ejector being operated by the electro-magnet in clependance of the movements of the masking frame.

It is also an important object of the present invention to provide a new enlarging easel wherein a member is adapted to hold the photographic paper fiat in position as well as to eject the paper after its being" exposed, and to serve as a marginal stop being arranged at right angles to a further stop and, together with the latter, adjustable to define the width of the blank maroi the sensitive paper.

A still further object of the invention is to provide a brake whereby the masking frame after being raised by the electro-magnct is arrested after an incipient downward movement until the positioned paper is clamped upon the plate; the frame can be lowered completely only after operating a key. It is hereby accomplished that during the positioning procedure of the photographic paper on the board the masking frame will not strike against the operators hand. Another execution of the braking device can comprise a piston which is operated by the maskor m ing frame and entering a cylinder causes gradua-l discharge of the enclosed medium in the beginning and thereupon suddenly effects the unhindered outflow of the medium and hereby the accelerated closing of the frame.

Details of the now preferred embodiment of the present invention are illustrated in the acdrawings and will be hereinafter more fully .escribed. Referring then to the drawings l is a perspective view of ferred embodiment of the invention, showing the enlarging easel with raised In sizing frame, relative to a portion of the base being broken away to expose interior parts.

Fig. 2 is a sectional View of 1 taken along the line A A, showing the clamping device and the ejector of the paper in the clamping position.

Fig. 3 is. a sectional according to 2 shot-vim. the same device in the jecting position.

Fig. 4 is a perspective view, having parts brohen away for clearness. illustrating the arrangement of the paper marginal stops within the base plate.

Fig. 5 is a fragmentary perspective view of the enlarging easel in the region of the mar-"Final stops with the base plate removed for clear-mess.

Fig. 6 is a sectional view of the enlarging easel illustrating a mechanic for the masking frame according to the present invention, the other parts left ofi for clearness.

Fig. 7 is a sectional detail view of a pneumatic brake to the masking frame according, to the present invention.

The enlarging easel comprises a base rear portion of which the mask frame 3 i tached, rotatably connected by a pivot 2. A plurality of slidable and fixable masking bands 3 are provided, carried on and co-operating with the mask frame 3 and adapted to define the sis of the. enlargements.

The pivot 2 of frame 3 is engaged with a gear 5 which operates a rack 6, mounted in the hollow of the base plate l, and carrying a soft iron armature slidably arranged to the interior portion or" the base i by means of guiding bolts .8.

the now prc- The said guiding bolts 3 are provided with springs Q, the resilient power of which adjustable to compensate the weight of the frame 3.

In front of the soft iron armature i an electromagnet it is arranged in the interior portion of base i, to be connected with a source of current by cable II, the latter being furnished with a foot switch it to operate the electro-niagnet iii. The armature 1 forms an extension 53 which 3 rests against the adjusting screw ill of a turning lever which is hOlll ntally pivoted to bracket the latter if idly mounted on Jase l. The lever is provided with an align-- lar icer ii to on a forlolilze rocker ill rotating round. the shaft it and being under pressure of sp 'ing whereby the portion of the rocker i9 opposite the lever arm ll is constantly pressed. downwards against the base i.

Referring to Figs. 2 and 3, wherein. the con bination of paper clampin de\' cc and ejector are illustrated, it will e n the rocker ii) at its end opposite the lever n l'l carries a shaft 2i upon which is pivoted e racket carrying the paper the stop 52 against the shop rock. it, the stop being p: an angle its winch press he enlar paper it the platen it! of the base plate I, when the ree if: in its lowest position. bracket 1:! of op has a which engages with a in nose its on adapted to anticloclr rctative movement one direction by grav ty. The lever when moved downward direction mark:

in 3 by an arrow, 3" fter certain stroke the nose 22a of bracket carrying stop and pushes it against nose her if;

of me e whereby bracket and stop rotate an iclockwise to eject the enlarging paper into a direction indicated in the drawing by the horizontal arrow. ejecting posit of stop it? is delineated in 8. T e recite it bovine returned to its initial position, the spring 24 pushes back. the stop 23, pressing it the shoulders of rocker Ill.

Accordingly to Figs. 1, 3 and 5 the bearii for the shaft 58 of rocker it are mounted on a slide which slides on. the sides of fixed member ill directly attached. to case i t in the opening Ella formed in cl latter carries the bearings 33*. for the member if rotatably mounted on the sltia" An arm pivoted on a bolt base i and connected with the bolt is adapted to be moved by a h to vary the s] movement of slide a allow this movement the corresponding portion of the side wall. of the base plate for 15 opening which covered by a bar furnished with a number of holes, if necessary gauged to mm., allowing to controllably vary the extention of the movement and to secure the various positions of said slide by inserting the lever into the respective boring.

Referring to Figs. and 5 a belt at is carried by the slide The said bolt 49 slides in a guiding slot lls of member ll, slidably arranged on shafts 2 journaled in the base, whereby the movers nt of slide commuted into a transverse movement of member ll carrying the paper stop (it; at right angles to stop The slot Ma in member ii cut at such an angle that for each movement of slide 38 operated by means of the adjusting arm the stops 23 and .3 move towards the centre of the paper board. at equal distances, whereby the width of the blank portion of the sensitive paper can be varied.

The paper stops 2;} and move within spaces 2% and. lilb between edge portions Zl'a of the opening 2lb cut into the platen ill, by which arrangeinent the enlarging paper it can. tightly be clamped. at any position of the adjustable marginal bands.

Referring to Fig. 6 the mask frame 3 is pivoted at 2 and provided with a cam 44, operating against the plane 45a of the follower it rotatably mounted on shaft All journaled to the base. The rocker-like two armed lever E8 is attached to shaft 5! journaled in the base, and forms on free end a key 52 which is operable through an opening 54 in the platen 2?. The lever acted upon by a spring 55 to press the free end of another lever All pivoted at 43 against follower M5. When the masl; frame is raised by the electro-magnet Ill, the lever so moved counterclockwise by the spring 55 and the end of the lever 51 is raised into engcc o with the follower 45 thereby preventing ace. dental closing of the mask frame by engaging the cam 44 thereof. The frame 3 is thus held open until the operator by the key 52 releases the follower The plane surface i tle is so designed that the A l and the end of the lever 41 are always within the range of the surface 46a when the follower rotated.

As shown by Figs. 1 and l the mask frame i. is pivotally connected to a piston slidably arranged in cylinder 51 which is journaled to the case I. The cylinder is provided with overflowchannels 58a and 5%, channel having a suostantially smaller, channel comparatively larger diameter. Cylinder El is, moreover, provided with a recoil valve 530 which allows the unhindered in-flow of a medium at the backward movement of the piston.

When the mask frame 3 is raised by means of the electro-magnet l2 and the latter switched off by foot-switch l2, the said frame is prevented from rotating downwards by piston which then operates within the range of the smaller over-flow channels 58a. When the p 55 reaches the portion of the cylinder where the wider dimension channels 5% are effective, the frame moves freely down. To facilitate unhampered movement to raise frame 3 the recoil valve 580 is arrangedv cylinder 5i.

As shown in Fig. 1 the 3 is pro vided with a finger 5% which. at t. upwards movement of the said frame engages pivoter lever 66 of a counter '6! connected to the base i so that the number of the enlar ements Ina-tie in this enlarging easel may be recorc ed.

In order to facilitate a clearer and fuller understanding of the matter of the present invention, the herein illustrated and now preferred embodiment thereof will be hereinafter prescribed as to its working manner.

It is assumed that the masking frame is closed, a sheet of sensitized paper is positioned under neath the masking bands A on the platen 2?, the exposure being effected.

At this position of the frame the soft iron armature has its largest distance from the pole shoes of the electro-magnet ill. The rocker i=3 under pressure of its spring as presses the angle 23a of the paper stop 23 on the enlarging paper. By switching on the electro magnet ill by means of the foot switch l2 the armature 'l is attracted concomitantly moving the rack 6 to the effect that by means of the gear 5 the mask frame is raised. The armature l imparts its movement by nose I3 and adjusting screw Hi to the lever i5 which with its arm ll pushes down rocker l9. By the rotative movement of the rocker l9 paper stop 23 and its angle 2364 are lifted to release the enlarging paper and cause their further movement the nose 22c, which is carried on bracket 22 to stop 23, to jerk against nose 23a of member 28 whereby bracket 22 and paper stop rotate on their shafts. The sudden rotative movement of the stop tosses the enlarging paper 26 off the platen. The thus ejected paper will suitably be gathered for further treatment.

The related proceedings are rapidly enacted by the action of the electro-magnet. The mask frame executes a rotative movement smaller than 90. The enlarging paper being ejected another sheet is positioned onto the platen 27 abutting the paper stops 23 and 48, whilst the electro magnet is switched on? by the foot switch I 2. The mask frame 3 rotates slowly down under the effect of its own weight which is not entirely balanced by the springs 9, and separates by means of gear 5 and rack 6 the armature from the poles of the electro-magnet Ill, which no longer engages the adjusting screw is of the lever 15. Rocker I9 under effect of spring 2:: swings back, whereby the paper stop is lowered, until the angle 23a clamps the enlarging paper on the paper support. Till this moment the mask frame has effected a slight rotative movement.

After clamping the paper 26 against the platen 21 the retarding effect of the follower 46, 46a takes place and the mask frame 3 will not freely move downwards until the key 52 The lowered mask frame 3 rests with its clamping bands 4 on the enlarging paper 25 and by its weight presses it firmly against the platen 2 After the exposure has taken place the electromagnet raises the mask frame and the paper is ejected according to the hereinabove mentioned manner. At each function of the masking frame the carrier 59 operates the counter.

If instead of the mechanic brake at, 46a for the mask frame 3 a pneumatic or hydraulic brake 55-582) is provided, the range of the overflow valves of small diameter 58a corresponds to the range of the rotating movement of the mask frame 3 up to shortly after the moment when the enlarging paper is clamped onto the platen 2?.

What is claimed is:

1. A photographic copying apparatus comprising a base, a fixed copy paper receiving platen therein spaced a distance above said base, a masking frame cover swingably pivoted at the rear side of said base to close by gravity upon said platen and paper thereon, an eleotrcmagnet including an anchor supported in the base below the platen, gearing means operatively connected to and between said electromagnetic anchor and the said cover to raise the latter into an open position when the electronagnet is energized, a mechanism positioned beneath the platen for clamping copy paper thereto when the cover is closed upon the platen and for ejecting the paper from the platen when the cover is raised comprising a vertically and laterally movable hook adapted to engage the paper, said hook extending from said mechanism beneath the platen through an opening therein to the surface of the platen, a two armed hook-supporting lever pivotis pushed down.

ed intermediate its ends beneath the platen, one arm of said lever forming a fork for pivotally supporting the said hook therein, the other arm of said two armed lever being free and extending forwardly beneath the platen, a spring acting upon said two armed lever to depress its said forked end and move the said hook vertically downward to clamp the paper to the platen, while said cover is being closed, an abutment supported independent of said forked end within the same in the path of vertical movement of the said hook to tip the latter laterally into a paper ejecting position when said cover is being raised, a right angled lever member pivoted to the said apparahis base, one arm of said member being adapted to contact and depress the said free end of the said two armed lever to move the latter upwardly against the said spring pressure to elevate the forked end thereof and the said hook into paper ejecting position, when said masking frame cover is being raised, said hook being tipped forwardly to eject the paper by hitting the said abutment as said hook is being elevated, the other arm of said right angled lever member being engaged by said electromagnet anchor to actuate said member as aforesaid, means for retarding the downward closing movement of said cover, a manually operated key to release said retarding means for quick closing of said cover and manually operated switch means to energize said electromagnet to attract the anchor to raise the said cover and simultaneously therewith actuate said right angled lever member to cause ejectment of the paper from the platen as aforsaid and to deenergize said electromagnet when said cover has reached its full open raised position.

2. An apparatus according to claim 1 including a slidably supported base support for said paper clamping and ejecting means, a copy paper side registering slide operatively connected to said slidable base support and a manually actuated lever pivoted to said slidable base support for simultaneously moving the same and the said side registering slide to place the copy paper in a selected exposure position on said platen and adjustable bands in said masking frame cover for adjusting the exposure opening therein to correspond with the registered position of the paper on the platen.

JOHANNES KEINATI-I. MANFRED KiiHN. FRIEDHELM BOSS. LUDWIG LEITZ.

References Cited in the file of this patent UNITED STATES PATENTS 

